<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Vue计算变量</title>
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    <style>
    </style>
</head>
<body>
    <div id="Application">     
    </div>
    <script>   
        const App = Vue.createApp({
            setup () {
                let a = Vue.ref(1);
                let b = Vue.ref(2);
                let sum = Vue.computed({
                    set (value){
                        a.value = value
                        b.value = value
                    },
                    get () {
                        return a.value + b.value
                    }
                });
                function click() {
                    a.value += 1;
                    b.value += 2;
                    if (sum.value > 10) {
                        sum.value = 0
                    } 
                }
                return {
                    sum,
                    click
                }
            },
            template:`
                <h1>测试数据：{{sum}}</h1>
                <button @click="click">点击</button>
            `
        })
        App.mount("#Application") 
    </script>
</body>
</html>